Pivotable articulation joint unlocking feature for surgical stapler

ABSTRACT

An apparatus comprises a body, a shaft assembly, an end effector, and an articulation joint. The end effector is operable to manipulate (e.g., staple) tissue. The articulation joint couples the end effector with the shaft assembly and permits the end effector to deflect away from the longitudinal axis of the shaft assembly. The articulation joint comprises a locking assembly, which is operable to selectively lock the angular position of the end effector relative to the longitudinal axis of the shaft assembly; and an unlocking feature. The unlocking feature is operable to selectively unlock the locking assembly. The shaft assembly further comprises a first movable member, which is operable to selectively drive articulation of the end effector at the articulation joint; and a second movable member, which is operable to selectively drive the unlocking feature. The second movable member is movable independently relative to the first movable member.

BACKGROUND

In some settings, endoscopic surgical instruments may be preferred overtraditional open surgical devices since a smaller incision may reducethe post-operative recovery time and complications. Consequently, someendoscopic surgical instruments may be suitable for placement of adistal end effector at a desired surgical site through the cannula of atrocar. These distal end effectors may engage tissue in a number of waysto achieve a diagnostic or therapeutic effect (e.g., endocutter,grasper, cutter, stapler, clip applier, access device, drug/gene therapydelivery device, and energy delivery device using ultrasonic vibration,RF, laser, etc.). Endoscopic surgical instruments may include a shaftbetween the end effector and a handle portion, which is manipulated bythe clinician. Such a shaft may enable insertion to a desired depth androtation about the longitudinal axis of the shaft, thereby facilitatingpositioning of the end effector within the patient. Positioning of anend effector may be further facilitated through inclusion of one or morearticulation joints or features, enabling the end effector to beselectively articulated or otherwise deflected relative to thelongitudinal axis of the shaft.

Examples of endoscopic surgical instruments include surgical staplers.Some such staplers are operable to clamp down on layers of tissue, cutthrough the clamped layers of tissue, and drive staples through thelayers of tissue to substantially seal the severed layers of tissuetogether near the severed ends of the tissue layers. Merely exemplarysurgical staplers are disclosed in U.S. Pat. No. 4,805,823, entitled“Pocket Configuration for Internal Organ Staplers,” issued Feb. 21,1989; U.S. Pat. No. 5,415,334, entitled “Surgical Stapler and StapleCartridge,” issued May 16, 1995; U.S. Pat. No. 5,465,895, entitled“Surgical Stapler Instrument,” issued Nov. 14, 1995; U.S. Pat. No.5,597,107, entitled “Surgical Stapler Instrument,” issued Jan. 28, 1997;U.S. Pat. No. 5,632,432, entitled “Surgical Instrument,” issued May 27,1997; U.S. Pat. No. 5,673,840, entitled “Surgical Instrument,” issuedOct. 7, 1997; U.S. Pat. No. 5,704,534, entitled “Articulation Assemblyfor Surgical Instruments,” issued Jan. 6, 1998; U.S. Pat. No. 5,814,055,entitled “Surgical Clamping Mechanism,” issued Sep. 29, 1998; U.S. Pat.No. 6,978,921, entitled “Surgical Stapling Instrument Incorporating anE-Beam Firing Mechanism,” issued Dec. 27, 2005; U.S. Pat. No. 7,000,818,entitled “Surgical Stapling Instrument Having Separate Distinct Closingand Firing Systems,” issued Feb. 21, 2006; U.S. Pat. No. 7,143,923,entitled “Surgical Stapling Instrument Having a Firing Lockout for anUnclosed Anvil,” issued Dec. 5, 2006; U.S. Pat. No. 7,303,108, entitled“Surgical Stapling Instrument Incorporating a Multi-Stroke FiringMechanism with a Flexible Rack,” issued Dec. 4, 2007; U.S. Pat. No.7,367,485, entitled “Surgical Stapling Instrument Incorporating aMultistroke Firing Mechanism Having a Rotary Transmission,” issued May6, 2008; U.S. Pat. No. 7,380,695, entitled “Surgical Stapling InstrumentHaving a Single Lockout Mechanism for Prevention of Firing,” issued Jun.3, 2008; U.S. Pat. No. 7,380,696, entitled “Articulating SurgicalStapling Instrument Incorporating a Two-Piece E-Beam Firing Mechanism,”issued Jun. 3, 2008; U.S. Pat. No. 7,404,508, entitled “SurgicalStapling and Cutting Device,” issued Jul. 29, 2008; U.S. Pat. No.7,434,715, entitled “Surgical Stapling Instrument Having MultistrokeFiring with Opening Lockout,” issued Oct. 14, 2008; U.S. Pat. No.7,721,930, entitled “Disposable Cartridge with Adhesive for Use with aStapling Device,” issued May 25, 2010; U.S. Pat. No. 8,408,439, entitled“Surgical Stapling Instrument with An Articulatable End Effector,”issued Apr. 2, 2013; and U.S. Pat. No. 8,453,914, entitled “Motor-DrivenSurgical Cutting Instrument with Electric Actuator Directional ControlAssembly,” issued Jun. 4, 2013. The disclosure of each of theabove-cited U.S. patents is incorporated by reference herein.

While the surgical staplers referred to above are described as beingused in endoscopic procedures, it should be understood that suchsurgical staplers may also be used in open procedures and/or othernon-endoscopic procedures. By way of example only, a surgical staplermay be inserted through a thoracotomy, and thereby between a patient'sribs, to reach one or more organs in a thoracic surgical procedure thatdoes not use a trocar as a conduit for the stapler. Such procedures mayinclude the use of the stapler to sever and close a vessel leading to alung. For instance, the vessels leading to an organ may be severed andclosed by a stapler before removal of the organ from the thoraciccavity. Of course, surgical staplers may be used in various othersettings and procedures.

Examples of surgical staplers that may be particularly suited or usethrough a thoracotomy are disclosed in U.S. patent application Ser. No.13/780,067, entitled “Surgical Instrument End Effector ArticulationDrive with Pinion and Opposing Racks,” filed Feb. 28, 2013; U.S. patentapplication Ser. No. 13/780,082, entitled “Lockout Feature for MovableCutting Member of Surgical Instrument,” filed Feb. 28, 2013; U.S. patentapplication Ser. No. 13/780,106, entitled “Integrated Tissue Positioningand Jaw Alignment Features for Surgical Stapler,” filed Feb. 28, 2013;U.S. patent application Ser. No. 13/780,120, entitled “Jaw ClosureFeature for End Effector of Surgical Instrument,” filed Feb. 28, 2013;U.S. patent application Ser. No. 13/780,162, entitled “SurgicalInstrument with Articulation Lock having a Detenting Binary Spring,”filed Feb. 28, 2013; U.S. patent application Ser. No. 13/780,171,entitled “Distal Tip Features for End Effector of Surgical Instrument,”filed Feb. 28, 2013; U.S. patent application Ser. No. 13/780,379,entitled “Staple Forming Features for Surgical Stapling Instrument,”filed Feb. 28, 2013; U.S. patent application Ser. No. 13/780,402,entitled “Surgical Instrument with Multi-Diameter Shaft,” filed Feb. 28,2013; and U.S. patent application Ser. No. 13/780,417, entitled“Installation Features for Surgical Instrument End Effector Cartridge,”filed Feb. 28, 2013. The disclosure of each of the above-cited U.S.patent applications is incorporated by reference herein.

While various kinds of surgical stapling instruments and associatedcomponents have been made and used, it is believed that no one prior tothe inventor(s) has made or used the invention described in the appendedclaims.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are incorporated in and constitute apart of this specification, illustrate embodiments of the invention,and, together with the general description of the invention given above,and the detailed description of the embodiments given below, serve toexplain the principles of the present invention.

FIG. 1 depicts a perspective view of an exemplary articulating surgicalstapling instrument;

FIG. 2 depicts a side elevational view of the instrument of FIG. 1;

FIG. 3 depicts a perspective view of an end effector of the instrumentof FIG. 1, with the end effector in a closed configuration;

FIG. 4 depicts a perspective view of the end effector of FIG. 3, withthe end effector in an open configuration;

FIG. 5 depicts an exploded perspective view of the end effector of FIG.3;

FIG. 6 depicts a cross-sectional end view of the end effector of FIG. 3,taken along line 6-6 of FIG. 4;

FIG. 7A depicts a cross-sectional side view of the end effector of FIG.3, taken along line 7-7 of FIG. 4, with the firing beam in a proximalposition;

FIG. 7B depicts a cross-sectional side view of the end effector of FIG.3, taken along line 7-7 of FIG. 4, with the firing beam in a distalposition;

FIG. 8 depicts a perspective view of the end effector of FIG. 3,positioned at tissue and having been actuated once in the tissue;

FIG. 9 depicts a schematic view of an exemplary control circuit for usein the instrument of FIG. 1;

FIG. 10 depicts a perspective view of the handle assembly of theinstrument of FIG. 1, with a housing half and some internal componentsremoved;

FIG. 11 depicts a perspective view of drive assembly components from thehandle assembly of FIG. 10;

FIG. 12 depicts a perspective view of an elongate member from the driveassembly of FIG. 11, coupled with the firing beam;

FIG. 13A depicts a top, perspective view of an exemplary alternativeshaft assembly that may be incorporated into the instrument of FIG. 1,with the end effector in a first position;

FIG. 13B depicts a top, plan view of the shaft assembly of FIG. 13A withthe end effector in a second articulated position;

FIG. 14 depicts a perspective view of the proximal end of the shaftassembly of FIG. 13A showing the articulation knob and internalkinematic components;

FIG. 15 depicts a top cross-sectional view of the proximal end of theshaft assembly of FIG. 13A taken along line 15-15 of FIG. 14;

FIG. 16 depicts a top, plan view of the shaft assembly of FIG. 13A in aneutral position;

FIG. 17 depicts a perspective, exploded view of the end effector and thearticulation joint of the shaft assembly of FIG. 13A;

FIG. 18A depicts a top, partially internal view of the articulationjoint of the shaft assembly of FIG. 13A in a first position;

FIG. 18B depicts a top, partially internal view of the articulationjoint of the shaft assembly of FIG. 13A with the first and second armsrotating a first cam member;

FIG. 18C depicts a top, partially internal view of the articulationjoint of the shaft assembly of FIG. 13A with the first and second armsrotating a second cam member and the first cam member further;

FIG. 18D depicts a top, partially internal view of the articulationjoint of the shaft assembly of FIG. 13A with a lock bar resilientlypositioning a lock tooth between teeth of the first cam member and thesecond cam member;

FIG. 18E depicts a top, partially internal view of the articulationjoint of the shaft assembly of FIG. 13A with the first and second armsrotating the first cam member yet even further;

FIG. 19 depicts a top plan, enlarged view of the interface of the cammembers and the lock bar of the shaft assembly of FIG. 13A;

FIG. 20 depicts a top plan, enlarged view of the interface of anexemplary alternative first cam member with the second cam member andthe lock bar of the shaft assembly of FIG. 13A;

FIG. 21A depicts a top plan, enlarged view of the articulation joint ofthe shaft assembly of FIG. 13A with an exemplary alternative first cammember;

FIG. 21B depicts a top plan, enlarged view of the articulation joint ofFIG. 21A with the first arm rotating the first cam member;

FIG. 21C depicts a top plan, enlarged view of the articulation joint ofFIG. 21A with the second arm rotating the second cam member;

FIG. 21D depicts a top plan, enlarged view of the articulation joint ofFIG. 21A with the first arm translated to re-lock the second cam member;

FIG. 22A depicts a top plan, enlarged view of the interface of anexemplary alternative cam member with the second cam member and the lockbar of the shaft assembly of FIG. 13A;

FIG. 22B depicts a top plan, enlarged view of the articulation joint ofFIG. 22A with the first arm rotating the cam member;

FIG. 23 depicts a top plan, enlarged view of an exemplary alternativearticulation joint with a first cam member having a wave cam;

FIG. 24 depicts a bottom perspective view of the first cam member ofFIG. 23;

FIG. 25A depicts a side cross-sectional view of the first cam member ofFIG. 23, taken along line 25-25 of FIG. 23, engaging with a second cammember and a vertically translatable lock bar, with the lock bar in alocked position;

FIG. 25B depicts a side cross-sectional view of the first cam member ofFIG. 23, taken along line 25-25 of FIG. 23, engaging with the second cammember and the lock bar, with the lock bar in an unlocked position;

FIG. 26A depicts a cross-sectional end view of the first cam member ofFIG. 23, taken along line 26-26 of FIG. 23, engaging the second cammember and the lock bar with, the lock bar in the locked position; and

FIG. 26B depicts a cross-sectional end view of the first cam member ofFIG. 23, taken along line 26-26 of FIG. 23, engaging the second cammember and the lock bar with the lock bar in the unlocked position.

The drawings are not intended to be limiting in any way, and it iscontemplated that various embodiments of the invention may be carriedout in a variety of other ways, including those not necessarily depictedin the drawings. The accompanying drawings incorporated in and forming apart of the specification illustrate several aspects of the presentinvention, and together with the description serve to explain theprinciples of the invention; it being understood, however, that thisinvention is not limited to the precise arrangements shown.

DETAILED DESCRIPTION

The following description of certain examples of the invention shouldnot be used to limit the scope of the present invention. Other examples,features, aspects, embodiments, and advantages of the invention willbecome apparent to those skilled in the art from the followingdescription, which is by way of illustration, one of the best modescontemplated for carrying out the invention. As will be realized, theinvention is capable of other different and obvious aspects, all withoutdeparting from the invention. Accordingly, the drawings and descriptionsshould be regarded as illustrative in nature and not restrictive.

I. Exemplary Surgical Stapler

FIG. 1 depicts an exemplary surgical stapling and severing instrument(10) that includes a handle assembly (20), a shaft assembly (30), and anend effector (40). End effector (40) and the distal portion of shaftassembly (30) are sized for insertion, in a nonarticulated state asdepicted in FIG. 1, through a trocar cannula to a surgical site in apatient for performing a surgical procedure. By way of example only,such a trocar may be inserted in a patient's abdomen, between two of thepatient's ribs, or elsewhere. In some settings, instrument (10) is usedwithout a trocar. For instance, end effector (40) and the distal portionof shaft assembly (30) may be inserted directly through a thoracotomy orother type of incision. It should be understood that terms such as“proximal” and “distal” are used herein with reference to a cliniciangripping handle assembly (20) of instrument (10). Thus, end effector(40) is distal with respect to the more proximal handle assembly (20).It will be further appreciated that for convenience and clarity, spatialterms such as “vertical” and “horizontal” are used herein with respectto the drawings. However, surgical instruments are used in manyorientations and positions, and these terms are not intended to belimiting and absolute.

A. Exemplary Handle Assembly and Shaft Assembly

As shown in FIGS. 1-2, handle assembly (20) of the present examplecomprises pistol grip (22), a closure trigger (24), and a firing trigger(26). Each trigger (24, 26) is selectively pivotable toward and awayfrom pistol grip (22) as will be described in greater detail below.Handle assembly (20) further includes an anvil release button (25), afiring beam reverse switch (27), and a removable battery pack (28).These components will also be described in greater detail below. Ofcourse, handle assembly (20) may have a variety of other components,features, and operabilities, in addition to or in lieu of any of thosenoted above. Other suitable configurations for handle assembly (20) willbe apparent to those of ordinary skill in the art in view of theteachings herein.

As shown in FIGS. 1-3, shaft assembly (30) of the present examplecomprises an outer closure tube (32), an articulation section (34), anda closure ring (36), which is further coupled with end effector (40).Closure tube (32) extends along the length of shaft assembly (30).Closure ring (36) is positioned distal to articulation section (34).Closure tube (32) and closure ring (36) are configured to translatelongitudinally relative to handle assembly (20). Longitudinaltranslation of closure tube (32) is communicated to closure ring (36)via articulation section (34). Exemplary features that may be used toprovide longitudinal translation of closure tube (32) and closure ring(36) will be described in greater detail below.

Articulation section (34) is operable to laterally deflect closure ring(36) and end effector (40) laterally away from the longitudinal axis(LA) of shaft assembly (30) at a desired angle (a). End effector (40)may thereby reach behind an organ or approach tissue from a desiredangle or for other reasons. In some versions, articulation section (34)enables deflection of end effector (40) along a single plane. In someother versions, articulation section (34) enables deflection of endeffector along more than one plane. In the present example, articulationis controlled through an articulation control knob (35) which is locatedat the proximal end of shaft assembly (30). Knob (35) is rotatable aboutan axis that is perpendicular to the longitudinal axis (LA) of shaftassembly (30). Closure ring (36) and end effector (40) pivot about anaxis that is perpendicular to the longitudinal axis (LA) of shaftassembly (30) in response to rotation of knob (35). By way of exampleonly, rotation of knob (35) clockwise may cause corresponding clockwisepivoting of closure ring (36) and end effector (40) at articulationsection (34). Articulation section (34) is configured to communicatelongitudinal translation of closure tube (32) to closure ring (36),regardless of whether articulation section (34) is in a straightconfiguration or an articulated configuration.

In some versions, articulation section (34) and/or articulation controlknob (35) are/is constructed and operable in accordance with at leastsome of the teachings of U.S. patent application Ser. No. 13/780,067,entitled “Surgical Instrument End Effector Articulation Drive withPinion and Opposing Racks,” filed Feb. 28, 2013, the disclosure of whichis incorporated by reference herein. Articulation section (34) may alsobe constructed and operable in accordance with at least some of theteachings of U.S. patent application No. [Attorney Docket NumberEND7429USNP.0614273], entitled “Articulation Drive Features for SurgicalStapler,” filed on even date herewith, the disclosure of which isincorporated by reference herein; and/or in accordance with the variousteachings below. Other suitable forms that articulation section (34) andarticulation knob (35) may take will be apparent to those of ordinaryskill in the art in view of the teachings herein.

As shown in FIGS. 1-2, shaft assembly (30) of the present examplefurther includes a rotation knob (31). Rotation knob (31) is operable torotate the entire shaft assembly (30) and end effector (40) relative tohandle assembly (20) about the longitudinal axis (LA) of shaft assembly(30). In some versions, rotation knob (31) is operable to selectivelylock the angular position of shaft assembly (30) and end effector (40)relative to handle assembly (20) about the longitudinal axis (LA) ofshaft assembly (30). For instance, rotation knob (31) may betranslatable between a first longitudinal position, in which shaftassembly (30) and end effector (40) are rotatable relative to handleassembly (20) about the longitudinal axis (LA) of shaft assembly (30);and a second longitudinal position, in which shaft assembly (30) and endeffector (40) are not rotatable relative to handle assembly (20) aboutthe longitudinal axis (LA) of shaft assembly (30). Of course, shaftassembly (30) may have a variety of other components, features, andoperabilities, in addition to or in lieu of any of those noted above. Byway of example only, at least part of shaft assembly (30) is constructedin accordance with at least some of the teachings of U.S. patentapplication Ser. No. 13/780,402, entitled “Surgical Instrument withMulti-Diameter Shaft,” filed Feb. 28, 2013, the disclosure of which isincorporated by reference herein. Other suitable configurations forshaft assembly (30) will be apparent to those of ordinary skill in theart in view of the teachings herein.

B. Exemplary End Effector

As also shown in FIGS. 1-3, end effector (40) of the present exampleincludes a lower jaw (50) and a pivotable anvil (60). Anvil (60)includes a pair of integral, outwardly extending pins (66) that aredisposed in corresponding curved slots (54) of lower jaw (50). Pins (66)and slots (54) are shown in FIG. 5. Anvil (60) is pivotable toward andaway from lower jaw (50) between an open position (shown in FIGS. 2 and4) and a closed position (shown in FIGS. 1, 3, and 7A-7B). Use of theterm “pivotable” (and similar terms with “pivot” as a base) should notbe read as necessarily requiring pivotal movement about a fixed axis.For instance, in the present example, anvil (60) pivots about an axisthat is defined by pins (66), which slide along curved slots (54) oflower jaw (50) as anvil (60) moves toward lower jaw (50). In suchversions, the pivot axis translates along the path defined by slots (54)while anvil (60) simultaneously pivots about that axis. In addition orin the alternative, the pivot axis may slide along slots (54) first,with anvil (60) then pivoting about the pivot axis after the pivot axishas slid a certain distance along the slots (54). It should beunderstood that such sliding/translating pivotal movement is encompassedwithin terms such as “pivot,” “pivots,” “pivotal,” “pivotable,”“pivoting,” and the like. Of course, some versions may provide pivotalmovement of anvil (60) about an axis that remains fixed and does nottranslate within a slot or channel, etc.

As best seen in FIG. 5, lower jaw (50) of the present example defines achannel (52) that is configured to receive a staple cartridge (70).Staple cartridge (70) may be inserted into channel (52), end effector(40) may be actuated, and then staple cartridge (70) may be removed andreplaced with another staple cartridge (70). Lower jaw (50) thusreleasably retains staple cartridge (70) in alignment with anvil (60)for actuation of end effector (40). In some versions, lower jaw (50) isconstructed in accordance with at least some of the teachings of U.S.patent application Ser. No. 13/780,417, entitled “Installation Featuresfor Surgical Instrument End Effector Cartridge,” filed Feb. 28, 2013,the disclosure of which is incorporated by reference herein. Othersuitable forms that lower jaw (50) may take will be apparent to those ofordinary skill in the art in view of the teachings herein.

As best seen in FIGS. 4-6, staple cartridge (70) of the present examplecomprises a cartridge body (71) and a tray (76) secured to the undersideof cartridge body (71). The upper side of cartridge body (71) presents adeck (73), against which tissue may be compressed when anvil (60) is ina closed position. Cartridge body (71) further defines a longitudinallyextending channel (72) and a plurality of staple pockets (74). A staple(77) is positioned in each staple pocket (74). A staple driver (75) isalso positioned in each staple pocket (74), underneath a correspondingstaple (77), and above tray (76). As will be described in greater detailbelow, staple drivers (75) are operable to translate upwardly in staplepockets (74) to thereby drive staples (77) upwardly through staplepockets (74) and into engagement with anvil (60). Staple drivers (75)are driven upwardly by a wedge sled (78), which is captured betweencartridge body (71) and tray (76), and which translates longitudinallythrough cartridge body (71). Wedge sled (78) includes a pair ofobliquely angled cam surfaces (79), which are configured to engagestaple drivers (75) and thereby drive staple drivers (75) upwardly aswedge sled (78) translates longitudinally through cartridge (70). Forinstance, when wedge sled (78) is in a proximal position as shown inFIG. 7A, staple drivers (75) are in downward positions and staples (77)are located in staple pockets (74). As wedge sled (78) is driven to thedistal position shown in FIG. 7B by a translating knife member (80),wedge sled (78) drives staple drivers (75) upwardly, thereby drivingstaples (77) out of staple pockets (74) and into staple forming pockets(64). Thus, staple drivers (75) translate along a vertical dimension aswedge sled (78) translates along a horizontal dimension.

It should be understood that the configuration of staple cartridge (70)may be varied in numerous ways. For instance, staple cartridge (70) ofthe present example includes two longitudinally extending rows of staplepockets (74) on one side of channel (72); and another set of twolongitudinally extending rows of staple pockets (74) on the other sideof channel (72). However, in some other versions, staple cartridge (70)includes three, one, or some other number of staple pockets (74) on eachside of channel (72). In some versions, staple cartridge (70) isconstructed and operable in accordance with at least some of theteachings of U. U.S. patent application Ser. No. 13/780,106, entitled“Integrated Tissue Positioning and Jaw Alignment Features for SurgicalStapler,” filed Feb. 28, 2013, the disclosure of which is incorporatedby reference herein. In addition or in the alternative, staple cartridge(70) may be constructed and operable in accordance with at least some ofthe teachings of U.S. patent application Ser. No. 13/780,417, entitled“Installation Features for Surgical Instrument End Effector Cartridge,”filed Feb. 28, 2013, the disclosure of which is incorporated byreference herein. Other suitable forms that staple cartridge (70) maytake will be apparent to those of ordinary skill in the art in view ofthe teachings herein.

As best seen in FIG. 4, anvil (60) of the present example comprises alongitudinally extending channel (62) and a plurality of staple formingpockets (64). Channel (62) is configured to align with channel (72) ofstaple cartridge (70) when anvil (60) is in a closed position. Eachstaple forming pocket (64) is positioned to lie over a correspondingstaple pocket (74) of staple cartridge (70) when anvil (60) is in aclosed position. Staple forming pockets (64) are configured to deformthe legs of staples (77) when staples (77) are driven through tissue andinto anvil (60). In particular, staple forming pockets (64) areconfigured to bend the legs of staples (77) to secure the formed staples(77) in the tissue. Anvil (60) may be constructed in accordance with atleast some of the teachings of U.S. patent application Ser. No.13/780,106, entitled “Integrated Tissue Positioning and Jaw AlignmentFeatures for Surgical Stapler,” filed Feb. 28, 2013; at least some ofthe teachings of U.S. patent application Ser. No. 13/780,120, entitled“Jaw Closure Feature for End Effector of Surgical Instrument,” filedFeb. 28, 2013; and/or at least some of the teachings of U.S. patentapplication Ser. No. 13/780,379, entitled “Staple Forming Features forSurgical Stapling Instrument,” filed Feb. 28, 2013, the disclosure ofwhich is incorporated by reference herein. Other suitable forms thatanvil (60) may take will be apparent to those of ordinary skill in theart in view of the teachings herein.

In the present example, a knife member (80) is configured to translatethrough end effector (40). As best seen in FIGS. 5 and 7A-7B, knifemember (80) is secured to the distal end of a firing beam (82), whichextends through a portion of shaft assembly (30). As best seen in FIGS.4 and 6, knife member (80) is positioned in channels (62, 72) of anvil(60) and staple cartridge (70). Knife member (80) includes a distallypresented cutting edge (84) that is configured to sever tissue that iscompressed between anvil (60) and deck (73) of staple cartridge (70) asknife member (80) translates distally through end effector (40). Asnoted above and as shown in FIGS. 7A-7B, knife member (80) also driveswedge sled (78) distally as knife member (80) translates distallythrough end effector (40), thereby driving staples (77) through tissueand against anvil (60) into formation. Various features that may be usedto drive knife member (80) distally through end effector (40) will bedescribed in greater detail below.

In some versions, end effector (40) includes lockout features that areconfigured to prevent knife member (80) from advancing distally throughend effector (40) when a staple cartridge (70) is not inserted in lowerjaw (50). In addition or in the alternative, end effector (40) mayinclude lockout features that are configured to prevent knife member(80) from advancing distally through end effector (40) when a staplecartridge (70) that has already been actuated once (e.g., with allstaples (77) deployed therefrom) is inserted in lower jaw (50). By wayof example only, such lockout features may be configured in accordancewith at least some of the teachings of U.S. patent application Ser. No.13/780,082, entitled “Lockout Feature for Movable Cutting Member ofSurgical Instrument,” filed Feb. 28, 2013, the disclosure of which isincorporated by reference herein; and/or at least some of the teachingsof U.S. patent application No. [Attorney Docket NumberEND7428USNP.0614271], entitled “Method of Using Lockout Features forSurgical Stapler Cartridge,” filed on even date herewith, the disclosureof which is incorporated by reference herein. Other suitable forms thatlockout features may take will be apparent to those of ordinary skill inthe art in view of the teachings herein. Alternatively, end effector(40) may simply omit such lockout features.

C. Exemplary Actuation of Anvil

In the present example, anvil (60) is driven toward lower jaw (50) byadvancing closure ring (36) distally relative to end effector (40).Closure ring (36) cooperates with anvil (60) through a camming action todrive anvil (60) toward lower jaw (50) in response to distal translationof closure ring (36) relative to end effector (40). Similarly, closurering (36) may cooperate with anvil (60) to open anvil (60) away fromlower jaw (50) in response to proximal translation of closure ring (36)relative to end effector (40). By way of example only, closure ring (36)and anvil (60) may interact in accordance with at least some of theteachings of U.S. patent application Ser. No. 13/780,120, entitled “JawClosure Feature for End Effector of Surgical Instrument,” filed Feb. 28,2013, the disclosure of which is incorporated by reference herein;and/or in accordance with at least some of the teachings of U.S. patentapplication No. [Attorney Docket Number END7430USNP.0614275], entitled“Jaw Opening Feature for Surgical Stapler,” filed on even date herewith,the disclosure of which is incorporated by reference herein. Exemplaryfeatures that may be used to provide longitudinal translation of closurering (36) relative to end effector (40) will be described in greaterdetail below.

As noted above, handle assembly (20) includes a pistol grip (22) and aclosure trigger (24). As also noted above, anvil (60) is closed towardlower jaw (50) in response to distal advancement of closure ring (36).In the present example, closure trigger (24) is pivotable toward pistolgrip (22) to drive closure tube (32) and closure ring (36) distally.Various suitable components that may be used to convert pivotal movementof closure trigger (24) toward pistol grip (22) into distal translationof closure tube (32) and closure ring (36) relative to handle assembly(20) will be apparent to those of ordinary skill in the art in view ofthe teachings herein. When closure trigger (24) reaches a fully pivotedstate, such that anvil (60) is in a fully closed position relative tolower jaw (50), locking features in handle assembly (20) lock theposition of trigger (24) and closure tube (32), thereby locking anvil(60) in a fully closed position relative to lower jaw (50). Theselocking features are released by actuation of anvil release button (25).Anvil release button (25) is configured and positioned to be actuated bythe thumb of the operator hand that grasps pistol grip (22). In otherwords, the operator may grasp pistol grip (22) with one hand, actuateclosure trigger (24) with one or more fingers of the same hand, and thenactuate anvil release button (25) with the thumb of the same hand,without ever needing to release the grasp of pistol grip (22) with thesame hand. Other suitable features that may be used to actuate anvil(60) will be apparent to those of ordinary skill in the art in view ofthe teachings herein.

D. Exemplary Actuation of Firing Beam

In the present example, instrument (10) provides motorized control offiring beam (82). FIGS. 9-12 show exemplary components that may be usedto provide motorized control of firing beam (82). In particular, FIG. 9shows an exemplary control circuit (100) that may be used to power anelectric motor (102) with electric power from a battery pack (28) (alsoshown in FIGS. 1-2). Electric motor (102) is operable to translatefiring beam (82) longitudinally as will be described in greater detailbelow. It should be understood that the entire control circuit (100),including motor (102) and battery pack (28), may be housed within handleassembly (20). FIG. 9 shows firing trigger (26) as an open switch,though it should be understood that this switch is closed when firingtrigger (26) is actuated. Circuit (100) of this example also includes asafety switch (106) that must be closed in order to complete circuit(100), though it should be understood that safety switch (106) is merelyoptional. Safety switch (106) may be closed by actuating a separatebutton, slider, or other feature on handle assembly (20). Safety switch(106) may also provide a mechanical lockout of firing trigger (26), suchthat firing trigger (26) is mechanically blocked from actuation untilsafety switch (106) is actuated.

Circuit (100) of the present example also includes a lockout switch(108), which is configured to be closed by default but is automaticallyopened in response to a lockout condition. By way of example only, alockout condition may include one or more of the following: the absenceof a cartridge (70) in lower jaw (50), the presence of a spent (e.g.,previously fired) cartridge (70) in lower jaw (50), an insufficientlyclosed anvil (60), a determination that instrument (10) has been firedtoo many times, and/or any other suitable conditions. Various sensors,algorithms, and other features that may be used to detect lockoutconditions will be apparent to those of ordinary skill in the art inview of the teachings herein. Similarly, other suitable kinds of lockoutconditions will be apparent to those of ordinary skill in the art inview of the teachings herein. It should be understood that circuit (100)is opened and thus motor (102) is inoperable when lockout switch (108)is opened. A lockout indicator (110) (e.g., an LED, etc.) is operable toprovide a visual indication of the status of lockout switch (108). Byway of example only, lockout switch (108), lockout indicator (110), andassociated components/functionality may be configured in accordance withat least some of the teachings of U.S. Pat. No. 7,644,848, entitled“Electronic Lockouts and Surgical Instrument Including Same,” issuedJan. 12, 2010, the disclosure of which is incorporated by referenceherein.

Once firing beam (82) reaches a distal-most position (e.g., at the endof a cutting stroke), an end-of-stroke switch (112) is automaticallyswitched to a closed position, reversing the polarity of the voltageapplied to motor (102). This reverses the direction of rotation of motor(102), it being understood that the operator will have released firingtrigger (26) at this stage of operation. In this operational state,current flows through a reverse direction indicator (114) (e.g., an LED,etc.) to provide a visual indication to the operator that motor (102)rotation has been reversed. In the present example, and as best seen inFIG. 12, a switch actuation arm (134) extends laterally from rack member(130), and is positioned to engage end-of-stroke switch (112) whenfiring beam (82) reaches a distal-most position (e.g., after tissue (90)has been severed and staples (77) have been driven into tissue (90)).Various other suitable ways in which end-of-stroke switch (112) may beautomatically switched to a closed position when firing beam (82)reaches a distal-most position will be apparent to those of ordinaryskill in the art in view of the teachings herein. Similarly, varioussuitable forms that reverse direction indicator (114) may take will beapparent to those of ordinary skill in the art in view of the teachingsherein.

Handle assembly (20) of the present example also includes a manualreturn switch (116), which is also shown in circuit (100). In thepresent example, return switch is activated by actuating reverse switch(27), which is shown on handle assembly (20) in FIG. 1. Manual returnswitch (116) may provide functionality similar to end-of-stroke switch(112), reversing the polarity of the voltage applied to motor (102) tothereby reverse the direction of rotation of motor (102). Again, thisreversal may be visually indicated through reverse direction indicator(114). In some versions, handle assembly (20) further includes amechanical return feature that enables the operator to manually reversefiring beam (82) and thereby retract firing beam (82) mechanically. Inthe present example, this manual return feature comprises a lever thatis covered by a removable panel (21) as shown in FIG. 1. Manual returnswitch (116) and the mechanical return feature are each configured toact as a “bailout” feature, enabling the operator to quickly beginretracting firing beam (82) proximally during a firing stroke. In otherwords, manual return switch (116) or the mechanical return feature maybe actuated when firing beam (82) has only been partially advanceddistally.

In some versions, one or more of switches (26, 106, 108, 112, 116) arein the form of microswitches. Other suitable forms will be apparent tothose of ordinary skill in the art in view of the teachings herein. Inaddition to or in lieu of the foregoing, at least part of circuit (100)may be configured in accordance with at least some of the teachings ofU.S. Pat. No. 8,210,411, entitled “Motor-Driven Surgical Instrument,”issued Jul. 3, 2012, the disclosure of which is incorporated byreference herein.

FIG. 10 shows motor (102) positioned within pistol grip (22) of handleassembly (20). Alternatively, motor (102) may be positioned elsewherewithin handle assembly (20). Motor (102) has a drive shaft (120) that iscoupled with a gear assembly (122). Thus, when motor (102) is activated,drive shaft (120) actuates gear assembly (122). As shown in FIG. 11,gear assembly (122) is in communication with a drive gear (124), whichmeshes with an idler pinion (126). Pinion (126) is disposed on a shaft(128) that is supported within handle assembly (20) and that is orientedparallel to drive shaft (120) of motor (102). Pinion (126) is furtherengaged with a rack member (130). In particular, pinion (126) mesheswith teeth (132) at the proximal end of rack member (130). Rack member(130) is slidably supported in handle assembly (20). It should beunderstood from the foregoing that, when motor (102) is activated, thecorresponding rotation of drive shaft (120) is communicated to pinion(126) via gear assembly (122), and the corresponding rotation of pinion(126) is converted to translation of rack member (130) by teeth (132).As shown in FIGS. 10-12, an elongate member (136) extends distally fromrack member (130). As shown in FIG. 12, a coupling member (138) joinsfiring beam (82) with elongate member (136). Rack member (130), elongatemember (136), coupling member (138), firing beam (82), and knife member(80) all translate together relative to handle assembly (20) in responseto activation of motor (102). In other words, activation of motor (102)ultimately causes firing beam (82) to translate longitudinally, thedirection of such translation depending on the direction of rotation ofdrive shaft (120).

It should be understood that a distal portion of elongate member (136),coupling member (138), and firing beam (82) extend through shaftassembly (30). A portion of firing beam (82) also extends througharticulation section (34). In some versions, rack member (130), elongatemember (136), and coupling member (138) are all substantially straightand rigid; while firing beam (82) has sufficient flexibility to bend atarticulation section (34) and translate longitudinally througharticulation section (34) when articulation section (34) is in a bent orarticulated state.

In addition to or in lieu of the foregoing, the features operable todrive firing beam (82) may be configured in accordance with at leastsome of the teachings of U.S. Pat. No. 8,453,914, the disclosure ofwhich is incorporated by reference herein. Other suitable components,features, and configurations for providing motorization of firing beam(82) will be apparent to those of ordinary skill in the art in view ofthe teachings herein. It should also be understood that some otherversions may provide manual driving of firing beam (82), such that amotor may be omitted. By way of example only, firing beam (82) may beactuated in accordance with at least some of the teachings of any otherreference cited herein.

FIG. 8 shows end effector (40) having been actuated through a singlestroke through tissue (90). As shown, cutting edge (84) (obscured inFIG. 8) has cut through tissue (90), while staple drivers (75) havedriven two alternating rows of staples (77) through the tissue (90) oneach side of the cut line produced by cutting edge (84). Staples (77)are all oriented substantially parallel to the cut line in this example,though it should be understood that staples (77) may be positioned atany suitable orientations. In the present example, end effector (40) iswithdrawn from the trocar after the first stroke is complete, the spentstaple cartridge (70) is replaced with a new staple cartridge (70), andend effector (40) is then again inserted through the trocar to reach thestapling site for further cutting and stapling. This process may berepeated until the desired amount of cuts and staples (77) have beenprovided. Anvil (60) may need to be closed to facilitate insertion andwithdrawal through the trocar; and anvil (60) may need to be opened tofacilitate replacement of staple cartridge (70).

It should be understood that cutting edge (84) may sever tissuesubstantially contemporaneously with staples (77) being driven throughtissue during each actuation stroke. In the present example, cuttingedge (84) just slightly lags behind driving of staples (77), such that astaple (47) is driven through the tissue just before cutting edge (84)passes through the same region of tissue, though it should be understoodthat this order may be reversed or that cutting edge (84) may bedirectly synchronized with adjacent staples (77). While FIG. 8 shows endeffector (40) being actuated in two layers (92, 94) of tissue (90), itshould be understood that end effector (40) may be actuated through asingle layer of tissue (90) or more than two layers (92, 94) of tissue.It should also be understood that the formation and positioning ofstaples (77) adjacent to the cut line produced by cutting edge (84) maysubstantially seal the tissue at the cut line, thereby reducing orpreventing bleeding and/or leaking of other bodily fluids at the cutline. Furthermore, while FIG. 8 shows end effector (40) being actuatedin two substantially flat, apposed planar layers (92, 94) of tissue, itshould be understood that end effector (40) may also be actuated acrossa tubular structure such as a blood vessel, a section of thegastrointestinal tract, etc. FIG. 8 should therefore not be viewed asdemonstrating any limitation on the contemplated uses for end effector(40). Various suitable settings and procedures in which instrument (10)may be used will be apparent to those of ordinary skill in the art inview of the teachings herein.

It should also be understood that any other components or features ofinstrument (10) may be configured and operable in accordance with any ofthe various references cited herein. Additional exemplary modificationsthat may be provided for instrument (10) will be described in greaterdetail below. Various suitable ways in which the below teachings may beincorporated into instrument (10) will be apparent to those of ordinaryskill in the art. Similarly, various suitable ways in which the belowteachings may be combined with various teachings of the references citedherein will be apparent to those of ordinary skill in the art. It shouldalso be understood that the below teachings are not limited toinstrument (10) or devices taught in the references cited herein. Thebelow teachings may be readily applied to various other kinds ofinstruments, including instruments that would not be classified assurgical staplers. Various other suitable devices and settings in whichthe below teachings may be applied will be apparent to those of ordinaryskill in the art in view of the teachings herein.

II. Exemplary Alternative Shaft Assembly

It will be appreciated that as a user urges instrument (10) into asurgical region, it may be desirable to approach the tissue to beclamped, stapled, or cut, from a particular angle. For instance, onceend effector (40) of instrument (10) is inserted through a trocar,thoracotomy, or other passageway for entering a surgical area, thetissue that the user wishes to target may be positioned out of reach orat an askew angle in relation to end effector (40) that is aligned withlongitudinal axis (LA) of shaft assembly (30). Thus, it may be desirablefor portions of instrument (10), such as end effector (40), toarticulate relative to longitudinal axis (LA) of shaft assembly (30) atan angle (a) (as seen in phantom in FIG. 1) such that the user canposition anvil (60) and lower jaw (50) of end effector (40) to squarelyor perpendicularly clamp against a vessel or other tissue. It willfurther be understood that articulating end effector (40) to squarelyposition end effector (40) against tissue may promote full seating andclamping of the tissue prior to cutting and stapling tissue. In additionto articulating, it may be desirable for end effector (40) to beselectively locked in a straight or articulated position such that aconstant manual bias by the user is not necessary to prevent endeffector (40) from pivoting or bending at articulation section (34). Itmay also be desirable to automatically lock upon articulation, withoutrequiring actuations of a separate articulation locking feature.

FIG. 13A depicts an exemplary alternative shaft assembly (200) that maybe readily incorporated with instrument (10) of FIG. 1. Shaft assembly(200) provides articulation and selective locking of articulationangles, as will be described in greater detail below. Shaft assembly(200) of the present example comprises a rotation knob (231),articulation control knob (235), and an end effector (240). Shaftassembly (200) also comprises end effector (240) positioned distally inrelation to a closure tube (232). End effector (240) includes anarticulation joint (234) which allows end effector (240) to articulatelaterally as will be described in further detail below. End effector(240) is substantially identical to end effector (40) of FIG. 1 exceptas otherwise described below.

Rotation knob (231) may be rotatably coupled with handle assembly (20)of FIG. 1 or any other suitable component (e.g., robotic controlinterface, etc.). Rotation knob (231) is operable to rotate shaftassembly (200) (including articulation control knob (235) and endeffector (240)) about the longitudinal axis (LA) defined by shaftassembly (200), relative to handle portion (20) (or relative to whateverelse rotation knob (231) is rotatably coupled with). This may be usefulin positioning end effector (240) at a desired angular orientation aboutthe longitudinal axis (LA).

A. Exemplary Articulation Control Features

Articulation control knob (235) is partially contained within anarticulation control knob casing (237). Casing (237) leads to closuretube (232). FIGS. 13A-B show shaft assembly (200) and an exemplarymovement of end effector (240) in response to turning of articulationcontrol knob (235). FIG. 13A shows articulation control knob (235) in afirst position where articulation control knob (235) and end effector(240) are both generally aligned along the longitudinal axis (LA) ofshaft assembly (200). The user may then manually rotate articulationcontrol knob (235) clockwise as seen in FIG. 13B to a second position.In response to the rotation of articulation control knob (235), endeffector (240) pivots or bends at articulation joint (234). as seen inFIG. 16B, to an articulation angle (a). In the present example, endeffector (240) articulates generally in the direction of the rotation ofarticulation control knob (235), though it will be understood that endeffector (240) may be configured to bend in the opposite direction ofthe rotation of articulation control knob (235). In other words, whenarticulation control knob (235) is rotated clockwise, end effector (240)laterally pivots clockwise as shown in FIG. 13B but could be configuredin some versions to pivot counter clockwise. FIG. 13B shows end effector(240) laterally pivoting clockwise slightly. It will be understood thatarticulation control knob (235) may be rotated further to cause endeffector (240) to laterally articulate further at articulation joint(234) to any suitable angle (a). For instance, end effector (240) maypivot until an approximately 90° angle is formed across articulationjoint (234). In some versions, end effector (240) may be operable topivot even further such that end effector (240) forms an acute angle inrelation to tube (232). Other suitable variations of end effector (240)pivoting will be apparent to one of ordinary skill in the art in view ofthe teachings herein. It should also be understood that articulationcontrol knob (235) may define the same angle with the longitudinal axis(LA) as the articulation angle (a) defined between end effector (240)and the longitudinal axis (LA). Such complementary angling may providethe operator with visual feedback exterior to the patient, indicatingthe articulation angle (a) of end effector (240).

The mechanics of the articulation of end effector (240) will bediscussed in further detail below. It will be appreciated thatarticulation control knob (235) may be rotated in the counter clockwisedirection to cause end effector (240) to articulate in a counterclockwise manner. Thus, depending on the desired direction and/or amountof articulation of end effector (240), the user can simply rotatearticulation control knob (235) of varying degrees in the direction thatthe user wishes end effector (240) to articulate to cause varyingdegrees of articulation of end effector (240).

FIG. 14 shows articulation control knob (235) with casing (237) removedto better show the inner workings of articulation control knob (235).Articulation control knob (235) is in communication with an articulationpinion (250). Articulation pinion (250) is in communication with a firstrack (252) and a second rack (256). First rack (252) is in communicationwith a first arm (242) through a first intermediate block (254), whereassecond rack (256) is in communication with a second arm (244) through asecond intermediate block (258). Arms (242, 244) are substantiallyparallel to each other in the present example. In particular, theproximal portions of arms (242, 244) (as shown in FIG. 18 and theportions of arms (242, 244) that extend through shaft assembly (200) areparallel to each other, though the proximal ends of arms (242, 244)flare slightly outwardly. Since arms (242, 244) are parallel to eachother along nearly their entire length (i.e., except for the distal-mostportions), arms (242, 244) may be readily recognized by those skilled inthe art as being “substantially parallel” to each other.

Articulation control knob (235) is unitarily coupled to articulationpinion (250). As a result, when the user turns articulation control knob(235), articulation pinion (250) rotates together with articulationcontrol knob (235). As articulation pinion (250) rotates, articulationpinion translates first rack (252) and second rack (256) accordingly inopposing directions. For instance, as seen in FIG. 15, articulationpinion (250) is in communication with first rack (252) and second rack(256) such that if articulation pinion (250) rotates clockwise, firstrack (252) retracts proximally away from end effector (240) whereassecond rack (256) advances distally toward end effector (240).Furthermore, when articulation pinion (250) rotates counter-clockwise,first rack (252) advances distally toward end effector (240) and secondrack (256) retracts proximally away from end effector (240). As firstrack (252) advances and retracts, first arm (242) advances and retractsin a similar manner. Similarly, as second rack (256) advances andretracts, second arm (244) also advances and retracts with second rack(256). Thus, rotating actuation control knob (235), which is connectedto articulation pinion (250), causes first arm (242) and second arm(244) to move back and forth with first rack (252) and second rack(256). Movement of first arm (242) and second arm (244) is operable tocause movement of other components in end effector (240), as will bediscussed in greater detail below.

FIG. 16 shows a larger view of end effector (240), including anvil(260). First arm (242) and second arm (244) are in communication with afirst cam member (330), which is pivotally disposed about a pin (379).As a result, advancing and retracting first arm (242) and second arm(244) causes first cam member (370) to rotate about cam holding pin(379), as will be described in further detail below.

FIG. 17 shows an exploded view of articulation joint (234). End effector(240) is disposed at the distal end of articulation joint (234). Endeffector (240) comprises an anvil (260) and lower jaw (268). It will beappreciated that end effector (240) is substantially similar to endeffector (40) of FIG. 1. Similar to lower jaw (50) of end effector (40),lower jaw (268) may receive a staple cartridge (not shown) which may besubstantially similar to staple cartridge (70). Additionally, similar toend effector (40) as described above, anvil (260) is driven toward lowerjaw (268) by advancing a closure ring (236) distally relative to endeffector (240). Closure ring (236) is driven longitudinally relative toend effector (240) based on translation of closure tube (232).Translation of closure tube (232) is communicated to closure ring (236)via articulation joint (234). Functionally, anvil (260) and lower jaw(268) are substantially similar to anvil (60) and lower jaw (50) of endeffector (40) with anvil (260) and lower jaw (268) working cooperativelyto contemporaneously sever and staple tissue as shown in FIG. 8 anddescribed above.

Articulation joint (234) comprises first cam member (330), second cammember (331), cam holding body (376), joint base (372), a lock bar (262)and a spring (364). First arm (242) distally terminates in a first hook(245), while second arm (244) distally terminates in a second hook(246). Hooks (245, 246) are in communication with cam openings (360) offirst cam member (330). As a result, when first arm (242) advancestoward end effector (240) and second arm (244) retracts, first cammember (330) rotates counter clockwise about holding pin (379). Whenfirst arm (242) instead retracts and second arm (244) advances towardend effector (240), first cam member (330) rotates clockwise aboutholding pin (379). Thus, as arms (242, 244) push and pull on camopenings (360) via hooks (245, 246) in an opposing fashion, first cammember (330) rotates accordingly as just described.

First cam member (330) is stacked on a second cam member (331). Secondcam member (331) and cam holding pin (379) are unitary features of camholding body (376). In some versions, second cam member (331) may beseparately constructed and fixedly coupled with cam holding body (376),such that as second cam member (331) rotates, cam holding body (376)rotates. Cam holding pin (379) is coaxially aligned with base opening(377) of joint base (372) along a pivot axis (380). Thus, first cammember (330) is rotatable about pivot axis (380), relative to second cammember (231) and cam holding body (376). Lock bar (262) is in selectivecommunication with first cam member (330) and second cam member (331),which will be described in greater detail below. Lock bar (262) isfurther in communication with spring (364), which distally biases lockbar (262). Joint base (372) is shaped to provide a seat and/or channelfor lock bar (262) to advance in. Lock bar (262) further includes a pairof bosses (387) operable to engage joint base (372) to restrict distalmotion of lock bar (262).

B. Exemplary Articulation of the Shaft Assembly

As discussed above, actuating articulation control knob (235) causesopposing advancement and retraction of arms (242, 244). It will beunderstood that this motion of arms (242, 244) rotates first cam member(330) about cam holding pin (279). As a result of rotating first cammember (330), second cam member (331) rotates with cam holding body(376. Thus, articulation joint (234) articulates, thereby pivoting endeffector (240) at articulation joint (234). In particular, cam holdingpin (379) and base opening (374) define a pivot axis (380), which isgenerally perpendicular to the longitudinal axis (LA) as noted above.End effector (240) pivots about pivot axis (380) in response to therotation of first cam member (330), which drives second cam member (331)as will be discussed below. In other words, pivot axis (380) serves asan axis for articulation of end effector (240) relative to shaftassembly (200). FIGS. 18A-E show the details of rotating first cammember (330) to drive the articulation of end effector (240).

FIG. 18A shows articulation joint (234) in a first position. Lock bar(262) is distally biased to engage second cam member (331). Inparticular, the distal end of lock bar (262) comprises a lock tooth(336) that fits between first cam teeth (333) and second cam teeth (335)and abuts second cam member (331), which can be seen in further detailin FIG. 19. As a result of the distal bias provided by spring (364),lock tooth (336) acts as a positive lock and thus maintains therotational position of second cam member (331). By maintaining therotational position of second cam member (331), lock bar (262) maintainsthe angular position of end effector (240) about pivot axis (380),thereby maintaining any articulation angle (a). First cam member (330)comprises a pair of cam wings (338, 339), and cam holding body (376)comprises a pair of bosses (371, 373). Bosses (371, 373) are unitaryfeatures of second cam member (331), such that as bosses (371, 373)rotate, second cam member (331) also rotates. It will be appreciatedthat in the first position of FIG. 18A, cam wings (338, 339) and bosses(371, 373) are not in contact. The interaction involving contact betweencam wings (338, 339) and bosses (371, 373) will be described in furtherdetail below with reference to FIGS. 18B-E. During a surgical operation,the user may guide shaft assembly (200) through a passageway (e.g.,trocar, thoracotomy, etc.) to reach the surgical area with end effector(240) in a straightened position as shown in FIG. 18A.

FIG. 19 shows an enlarged view of lock tooth (336) in the position shownin FIG. 18A. As can be seen, lock tooth (336) has generally straightparallel sides (386) that are configured to fit between first cam teeth(333) and second cam teeth (335). The distal end of lock tooth (336) hasa rounded tip (385) with angled sides (381) leading to parallel sides(386). Each tooth (335) of second cam teeth (335) comprises generallystraight parallel sides (383) and angled sides (384). Parallel sides(383) are configured to engage parallel sides (386) of lock tooth (336)to prevent lock tooth (336) from riding along second cam teeth (335)without assistance from first cam member (330). This engagement betweenat least one side (383) and at least one side (386) also prevents camholding body (376) from rotating about pivot axis (380), therebypreventing end effector (240) from pivoting at articulation joint (234).

Once first cam member (330) rotates as shown in FIGS. 18B-C and as willbe described in greater detail below, a triangular tooth (333) of firstcam member (330) will cam against angled sides (381), and will therebydive lock bar (262) proximally in response to first cam (330) rotating.It should be understood that tooth (333) may have a variety of differentshapes other than triangular. Some exemplary alternative shapes will bedescribed in greater detail below, while others will be apparent tothose of ordinary skill in the art in view of the teachings herein. Locktooth (336) moves proximally sufficiently such that angled sides (381)of lock tooth (336) can eventually engage and ride along angled sides(384) of second cam teeth (335) as first cam member (330) continues torotate and as second cam member (331) rotates. This provides furthercamming action to drive lock bar (262) proximally. Once lock tooth (336)traverses angled sides (384) of second cam teeth (335), then lock tooth(336) returns distally to a position between the next pair of first camteeth (333) and second cam teeth (335) similar to the positioning shownin FIG. 19. For illustrative purposes, advancing lock tooth (336)between one set of first cam teeth (333) and second cam teeth (335) maybe considered one articulation increment. As lock tooth (336) distallyadvances, lock tooth (336) strikes second cam member (331) betweensecond cam teeth (335). It will be understood that lock tooth (336) neednot necessarily extend far enough to strike second cam member (331). Forinstance, lock tooth (336) may only extend distally such that parallelsides (383) prevent lock tooth (336) from riding along second cam member(331) without assistance from first cam teeth (333). In the illustratedversion, bosses (387) engage joint base (382) to prevent further distalmotion of lock bar (262).

As noted above, the operator may wish to pivot end effector (240) atarticulation joint (234) to better position end effector (240) inrelation to targeted tissue. FIG. 18B shows a second stage of actuationfor articulation joint (234) to move to in response to turningarticulation control knob (235) shown in FIG. 14. In the illustratedversion, the user has turned articulation knob (235) counter clockwise,which rotates articulation pinion (250) as well. As articulation pinion(250) rotates counter clockwise, first rack (252) moves distally andsecond rack (256) moves proximally in relation to end effector (240).Accordingly, first arm (242) and second arm (244) as shown in FIG. 18Bmove such that first arm (242) advances toward end effector (240) andsecond arm (244) retracts away from end effector (240). It will beappreciated that the distal portions of first arm (242) and second arm(244) of the illustrated version are not positioned parallel in relationto each other. Instead, first arm (242) and second arm (244) areobliquely angled in relation to each other, though it will be understoodthat first arm (242) and second arm (244) could be positioned parallelto each other.

Movement of arms (242, 244) as seen in FIG. 18B causes first cam member(330) to rotate counter clockwise about pivot axis (380). As first cammember (330) rotates, two actions occur in a generally simultaneousmanner. First, cam teeth (330) have a triangular shape that urges lockbar (262) proximally away from end effector (240) through a cammingaction as a result of first cam teeth (333) engaging angled sides (381).Again, teeth (333) may have a variety of different shapes other thantriangular. Spring (364) compresses to accommodate proximal motion oflock bar (262). As a result, rounded tip (385) moves proximallysufficient to traverse parallel sides (383). Additionally, cam wings(338, 339) rotate counter clockwise with first cam member (330). As aresult of the rotation, cam wing (339) removes gap (361) between boss(373) and engages boss (373). Meanwhile, cam wing (338) movesrotationally away from boss (371). It will be understood that whilefirst cam member (330) and lock bar (262) have moved in response to themovement of arms (242, 244) during the transition from the configurationshown in FIG. 18A to the configuration shown in FIG. 18B, second cammember (331) and accordingly end effector (240) have not yet moved.Thus, end effector (240) remains in a straight orientation at thisstage.

FIG. 18C shows a third stage of actuation of articulation joint (234).It will be understood that the user continues to rotate articulationcontrol knob (235) in an effort to articulate end effector (240). Arms(242, 244) continue to move such that first arm (242) moves distally andsecond arm (244) moves proximally. Movement of arms (242, 244) continuesto rotate first cam member (330), which causes cam wing (339) torotationally move further thereby urging boss (373) to rotationally moveas well. Since boss (273) is unitary with second cam member (331),second cam member (331) begins to rotate. As second cam member rotates(331), lock bar (262) moves further proximally as a result of angledsides (384) camming against angled sides (381) of lock tooth (336).Thus, lock tooth (236) rides along second cam teeth (335). Second cammember (331) rotates until tip (388) of second cam member (331) engagesrounded tip (385). Second cam teeth (335) have parallel sides (383) suchthat angled edges (381) of lock tooth (336) can engage angled sides(284) only after first cam teeth (333) urges lock tooth (336) proximallysuch that rounded tip (385) traverses parallel sides (383). Prior toriding along first cam teeth (333), lock tooth (336) is generally unableto ride along second cam teeth (335) due to parallel sides (383)engaging parallel sides (386). It will further be appreciated that aslock tooth (336) rides along angled sides (384), lock tooth (336)disengages first cam teeth (333). As also seen in FIG. 18C, lock bar(262) and lock tooth (336) have moved to a proximal most position withjust second cam teeth tip (388) being in contact with lock tooth (336).Also as a result of rotation of second cam member (331), cam holdingbody (376) and accordingly, closure ring (236), which leads to endeffector (240), articulate in a counter clockwise direction.

FIG. 18D shows a fourth stage of actuation for articulation joint (234).Once again, it will be understood that user is continuing to rotatearticulation control knob (235) in an effort to cause furtherarticulation of end effector (240). Arms (242, 244) continue to movesuch that first arm (242) moves distally further and second arm (244)moves proximally further. Movement of arms (242, 244) continues torotate first cam member (330), which causes cam wing (339) to push boss(373) rotationally further. Lock tooth (336) continues to ride alongsecond cam teeth (335) until the distal bias caused by spring (364)urges lock bar (262) into the position shown in FIG. 18D. It will beappreciated that when lock bar (262) snaps into the position shown inFIG. 18D, an audible click or snap may be heard or felt. As a result,the user receives audible and/or tactile confirmation that lock tooth(336) has moved from between one set of cam teeth (333, 335) to anotheror otherwise has rotated by a single articulation increment. When in theposition shown in FIG. 18D, first cam member (330) stops rotating andlock tooth (236) fits between cam teeth (333, 335). Closure ring (236)and accordingly end effector (240) stop articulating. A positive lockhas formed because any rotational motion of second cam member (331)urged by transverse forces on end effector (240) would result inparallel sides (386) engaging parallel sides (383) and stopping anyfurther rotation of second cam member (331), which locks thearticulation of end effector (240). It should be understood that thetransition from the configuration shown in FIG. 18A to the configurationshown in FIG. 18D represents articulation through one articulationincrement, or increment of articulation motion, in which the distance isdefined generally by the spaces between second cam teeth (335).

It will be understood that in the position shown in FIG. 18D, endeffector (240) has articulated thereby providing the user with a shaftassembly (200) with an articulated end effector (240). It will beappreciated that the user may wish to use shaft assembly (200) in theposition shown in FIG. 18D or may wish to pivot end effector (240)further by one or more additional articulation increments. In the eventthat the user does not rotate articulation knob (235) further, thelocking of lock tooth (336) between first cam teeth (333) and second camteeth (335) prevents end effector (240) from pivoting to return to astraight position. Once end effector (240) has been articulated to adesired angle (a), it will be understood that the user may actuatefiring beam (282) to drive knife member (280) to cut and drive staples(77) through tissue. For instance, knife member (280) and firing beam(282) may be in communication through, for instance, a bendable beamsuch that firing beam (282) can advance through any degree of pivot ofarticulation joint (234).

FIG. 18E shows a fifth stage of actuation for articulation joint (234)in the event that the user wishes to pivot end effector (240) further.Once again, it will be understood that user continues to rotatearticulation control knob (235). As a result, arms (242, 244) continueto move such that first arm (242) moves distally further and second arm(244) moves proximally further. Movement of arms (242, 244) continues torotate first cam member (330), which causes cam wing (339) to push boss(373) rotationally. First cam member (330) and second cam member (331)move similarly as shown in FIGS. 18B-D, which causes end effector (240)to articulate further as well as lock in a more articulated position. Itwill be understood that the user may continue to rotate articulationcontrol knob (235) to cause end effector (240) to pivot as far as theuser desires. Furthermore, the user may rotate articulation control knob(235) in the opposite direction to cause arms (242, 244) and cam members(330, 331) to move in the opposite direction, thereby causing endeffector (240) to articulate in an opposite direction.

As seen in the exemplary actuation shown in FIGS. 18A-18E, first cammember (330) is operable to unlock articulation joint (234) and pivotend effector (240) at articulation joint (234) about pivot axis (380),by transferring motion from arms (242, 244) to first cam member (330).In addition, second cam member (331) and lock bar (262) cooperate tolock articulation joint (234), to thereby lock the angle (a) of endeffector (240) relative to the longitudinal axis (LA) of shaft assembly(200).

III. Exemplary Alternative Articulation Joints

In some instances, it may be desirable to provide alternative structuresand methods for selectively locking and unlocking articulation joint(234). It may also be desirable to modify the structures and methodsthat are used to drive articulation joint (234) based on the alternativestructures and methods that are used to selectively lock and unlockarticulation joint (234). Various examples of alternative structures andmethods that may be used to provide selective locking and unlocking ofan articulation joint are described in greater detail below, while otherexamples will be apparent to those of ordinary skill in the art in viewof the teachings herein. Similarly, various examples of alternativestructures and methods that may be used to drive an articulation jointare described in greater detail below, while other examples will beapparent to those of ordinary skill in the art in view of the teachingsherein. It should be understood that the following examples may bereadily incorporated into articulation joint (234); or be readilyeincorporated into shaft assembly (200) in place of articulation joint(234). Various suitable ways in which the following examples may beincorporated into instrument (10) will be apparent to those of ordinaryskill in the art.

A. Exemplary Square Toothed Cam member

FIG. 20 shows an exemplary alternative first cam member (430). First cammember (430) fits into articulation joint (234) and has functionalitythat is substantially the same as that of first cam member (330) asshown in FIGS. 18A-E and as described above. For instance, like withfirst cam member (234), first cam member (430) is configured to firstrotate relative to second cam member (331) to translate lock bar (262)proximally by engaging angled sides (381) of lock bar (262). Lock bar(262) may then be translated to a sufficient proximal distance such thatangled sides (384) of second cam teeth (335) may engage angled sides(381) of lock tooth (336) (see, e.g., FIGS. 18A-C and accompanyingdiscussion, above). However, unlike first cam member (330), first cammember (430) comprises square teeth (433) rather than triangular teeth(333).

It should be understood that lock tooth (336) of lock bar (262) maycomprise a reconfigured shape to account for the differences betweenengaging a square tooth (433) and a triangular tooth (333). Forinstance, angled sides (381) of lock tooth (336) may extend for agreater distance relative to straight parallel sides of lock tooth(336). Of course, the particular geometry of lock tooth (336) will varyin relation to the size of first cam tooth (433) relative to the sizeand shape of second cam tooth (335) as will be apparent to those ofordinary skill in the art in view of the teachings herein.

B. Exemplary First Cam member with Single Cam

FIGS. 21A-D show an exemplary alternative first cam member (530) thatmay be incorporated into articulation joint (234). First cam member(530) is pivotally disposed on holding pin (379). First cam member (530)is asymmetric about a central axis that runs parallel to thelongitudinal axis (LA) of shaft assembly (200). First cam member (530)and second cam member (331) rotate independently about axis (380)defined by holding pin (379). In the present example, first cam member(530) is configured with a single cam (533) rather than cam teeth (433,333) as described with respect to first cam members (430, 330). Singlecam (533) is formed as a proximally oriented lobe. First cam member(530) is operable to rotate by a force applied by first arm (242), thusadvancing single cam (533) of first cam member (530) relative to lockbar (262) to translate lock bar (262) proximally. Single cam (533) offirst cam member (530) may translate lock bar (262) to a point wherelock bar (262) either no longer engages second cam teeth (335) of secondcam member (331), or angled sides (384) of second cam teeth (335) mayengage angled sides (381) of lock tooth (336). Accordingly, articulationjoint (234) may then be articulated by the rotation of second cam member(331) (which is unitarily attached to end effector (240)) via thetranslation of arms (242, 244) in opposing directions in a way similarto that described above with first cam member (330).

In some versions, arms (242, 244) may be translated independently ofeach other. For instance, first arm (242) may be operable to translateproximally or distally to rotate first cam member (530) to selectivelylock and unlock second cam member (331) with lock bar (262). Second arm(244) may likewise be operable to translate proximally or distally torotate second cam member (331) independently of the rotation of firstcam member (530). As can be seen in FIG. 21B, first arm (242) maytranslate proximally to rotate first cam member (530) relative to secondcam member (331), thus translating lock bar (262) proximally via singlecam (533) to disengage lock bar (262) from second cam member (331).Next, as can be seen in FIG. 21C, second arm (244) may then betranslated distally or proximally to articulate articulation joint (234)clockwise or counter clockwise, respectively. FIG. 21D shows that, oncearticulation joint (234) is articulated to a desired angle (a) relativeto the longitudinal axis (LA) of shaft assembly (200), articulationjoint (234) may be locked in place. In particular, first arm (242) maybe translated distally to rotate first cam member (530) in a counterclockwise rotation to bring single cam (533) out of engagement with lockbar (262). In other words, in the transition from the state shown inFIG. 21C to the state shown in FIG. 21D, first cam member (530) nolonger bears proximally against lock bar (262), such that coil spring(364) drives lock bar (262) distally back to a position where lock bar(262) locks the angular position of second cam member (331). With endeffector (240) being unitarily secured to second cam member (331) asnoted above, the distally positioned lock bar (262) locks the angularposition of end effector (240).

It should be understood that in examples where arms (242, 244) areindependently translated, articulation control knob (235) may utilize ameans for articulation other than a rack and pinion apparatus asdescribed above and shown in FIGS. 14-15; or arms (242, 244) couldutilize separate racks and pinions. For instance, in some examples,articulation control knob (235) may be connected to an electromechanicalcontrol system utilizing one or more motors and switches. Yet in otherexamples, articulation control knob (235) may translate only second arm(244) while first arm (242) may be translated with a separatelock/unlock switch, slider, or lever. Of course, arms (242, 244) may beindependently translated using any other suitable means as will beapparent to those of ordinary skill in the art in view of the teachingsherein.

C. Exemplary Articulation Joint with “Pi” Shaped Cam

FIGS. 22A-B show an exemplary alternative articulation joint (634) whichutilizes a “Pi” shaped cam member (630) to lock and unlock articulationof end effector (240) at articulation joint (634). Articulation joint(634) may be readily incorporated into shaft assembly (200). Inparticular, articulation joint comprises cam member (630), second cammember (631), a resiliently biased lock bar (662), a first arm (642),and a second arm (644). Cam member (630) is rotatable about a pivot pin(622) such that cam member (630) is independently rotatable relative tosecond cam member (631). Cam member (630) comprises two proximallyextending protrusions (623) that are configured to cam against a locktooth (636) of lock bar (662). Lock bar (662) is resiliently biaseddistally such that lock tooth (636) of lock bar (662) engages cam teeth(635) of second cam member (631) thereby locking articulation joint(634). Second cam member (631) is rotatable about pin (679) and isunitarily connected to end effector (240) such that second cam member(631) may articulate articulation joint (634) when lock bar (662) isdisengaged from second cam member (631), as will be described in greaterdetail below. Second cam member (631) and lock bar (662) are similar tosecond cam member (331) and lock bar (262), respectively.

FIG. 22B shows an exemplary operational state of articulation joint(634). As can be seen, protrusions (623) of cam member (630) areconfigured to cam and thereby drive lock tooth (636) of lock bar (662)such that lock bar (662) is partially translated by cam member (630).Such translation of lock bar (662) is achieved by independent actuationof first arm (642) in the proximal direction. It should be understoodthat first arm (642) may also be actuated in the distal direction toachieve the same result. Additionally, in other examples, second arm(644) may actuate cam member (630) instead of first arm (642).

With lock bar (662) partially translated in the proximal direction, suchthat second cam member (631) is unlocked by lock bar (662), second cammember (631) may be rotated about pin (679) via second arm (644). Ofcourse, as described above with respect to cam member (630), second cammember (631) may be rotated using first arm (642) instead of second arm(644). Lock bar (662) may be translated further in the proximaldirection by angled sides (684) of second cam member (631) cammingagainst angled sides (681) of lock bar (662). Thus, second cam member(631) may be rotated from one cam tooth (635) to the next cam tooth(635) similar to second cam member (331) described above. It should beunderstood that because cam member (630) is independently rotatableabout pivot pin (622), cam member (630) may remain substantially alignedwith lock bar (662) as second cam member (631) is rotated from one camtooth (635) to the next cam tooth (635). Accordingly, first arm (642)may be translated again, pivoting cam member (630) back to the positiondepicted in FIG. 22A. A spring (not shown) or other resilient member maythen drive lock tooth (636) distally back to the position depicted inFIG. 22A, thereby locking the angular position of end effector (240) atarticulation joint (634).

D. Exemplary Articulation Joint with Wave Shaped Cam

FIGS. 23-26B show an exemplary alternative articulation joint (734) ofshaft assembly (200). In the present example, articulation joint (734)is substantially similar to articulation joint (234) in thatarticulation joint (734) utilizes a first cam member (730) and a lockbar (762) to lock and unlock a second cam member (731) and therebyarticulate end effector (240) relative to the longitudinal axis (200) ofshaft assembly (200). Although not shown in FIGS. 23-26B, it should beunderstood that second cam member (731) may be unitarily attached to endeffector (240) such that rotation of second cam member (731) articulatesend effector (240). Second cam member (731) and lock bar (762) may bestructurally similar to second cam member (331) and lock bar (262) asdescribed above with respect to articulation joint (234). However, aswill be described below, second cam member (731) and lock bar (762) mayoperate in a different manner to articulate end effector (240) ascompared to articulation joint (234) discussed above. First cam member(730) and second cam member (731) are both partially rotatable about apin (735). End effector (240) is rotatable about the longitudinal axisdefined by pin (735) to articulate end effector (240).

As can best be seen in FIG. 24 (showing first cam member (730) upsidedown relative to FIG. 23), unlike first cam member (330), first cammember (730) comprises a wave surface (727) that is obliquely orientedrelative to the top and bottom surfaces (725, 726) of first cam member(730). Also unlike cam member (330), which provides longitudinaltranslation of lock bar (262), first cam member (730) of this exampleprovides vertical movement of lock bar (762) based on the configurationof wave surface (727). In other words, while lock bar (262) travelsalong a longitudinal path that is parallel to the longitudinal axis (LA)of shaft assembly (200) to provide selective locking and unlocking, lockbar (762) travels along a vertical path that is transverse to thelongitudinal axis (LA) of shaft assembly (200) to provide selectivelocking and unlocking. This vertical movement of lock bar (762) providesselective locking of second cam member (731) based on whether lock bar(762) is in a lower vertical position (locked—FIGS. 25A and 26A) or anupper vertical position (unlocked—FIGS. 25B and 26B). In the presentexample, lock bar (762) moves along a vertical plane that passes throughboth the longitudinal axis (LA) of shaft assembly (200) and thelongitudinal axis of pin (735). In some other versions, lock bar (762)moves along a vertical plane that is parallel to the vertical plane thatpasses through both the longitudinal axis (LA) of shaft assembly (200)and the longitudinal axis of pin (735).

In some versions, the proximal end of lock bar (762) is pivotallycoupled with a mounting surface (722) of shaft assembly (200), and thedistal end of lock bar (762) pivots vertically about that pivotalcoupling in order to provide the selective locking and unlocking ofarticulation joint (734). In some other versions, the entire length oflock bar (762) travels along a vertical path relative to mountingsurface (722) of shaft assembly (200) in order to provide the selectivelocking and unlocking of articulation joint (734). In either version,lock bar (762) may be resiliently biased upwardly relative to mountingsurface (722) of shaft assembly (200). For instance, FIGS. 25A-25B showa coil spring (721) being interposed between a distal portion of lockbar (762) and mounting surface (722), such that coil spring (721)provides the upward bias. In some other versions (e.g., those where theproximal end of lock bar (762) is pivotally coupled with mountingsurface (722)), a torsion spring may be used to provide the upward bias.Still other suitable ways in which lock bar (762) may be resilientlybiased will be apparent to those of ordinary skill in the art in view ofthe teachings herein.

It should be understood from the foregoing that, as first cam member(730) rotates, wave surface (727) is operable to either cam lock bar(762) downwardly or provide clearance for spring (721) to drive lock bar(762) upwardly, depending on the angular position of first cam member(730). Comparing FIG. 23 with FIGS. 25A-B shows an exemplary operationof articulation joint (734). In particular, as can be seen in FIGS. 23,25A, and 26A, lock bar (762) is urged downwardly by a crest portion(728) of wave surface (727) such that lock bar (762) is engaging secondcam member (731). It should be understood that in the configurationdepicted in FIG. 25A, articulation joint (734) is in a lockedconfiguration such that the angular articulation position of endeffector (240) is fixed.

To unlock end effector (240), first cam member (730) may be rotated viaa first and second arm (742, 744), thereby rotating a trough portion(729) of wave surface (727) toward lock bar (762). As trough portion(729) rotates toward lock bar (762), lock bar (762) may begin to travelupwardly toward the position shown in FIGS. 25B and 26B. As can be seenin FIG. 25B, lock bar (762) is received in trough portion (729) of wavesurface (727) and is accordingly pivoted to the upward most position.Likewise, lock bar (762) no longer engages second cam member (731) whenlock bar (762) is in this upper position. Thus, in the configurationshown in FIG. 25B, second cam member (731) is unlocked such that endeffector (240) may be permitted to deflect laterally away from thelongitudinal axis (LA) of shaft assembly (200).

It should be understood, that similar to articulation joint (234),articulation joint (734) may be equipped with cam wings (738, 739) andbosses (771, 773) to cause first cam member (730) to rotateindependently initially; and with second cam member (731) at a laterpoint in rotation. In other examples, cam wings (738, 739) and bosses(771, 773) may be omitted entirely and arms (742, 744) may beindependently actuated to drive the rotation of first cam member (730)and second cam member (731) independently as described above withrespect to first cam member (530). Of course any other suitable methodof causing first cam member (730) followed by the later rotation ofsecond cam member (731) may be used as will be apparent to those ofordinary skill in the art in view of the teachings herein.

Once second cam member (731) has been articulated to an articulatedposition by arms (742, 744), first cam member (730) may be rotatedfurther to transition second cam member (731) back to the lockedposition shown in FIGS. 25A and 26A. In particular, first cam member(730) may be rotated such that crest portion (728) drives lock bar (762)downwardly back into engagement with second cam member (731). It shouldbe understood that in such a configuration, a gap between two lock teeth(733) of second cam member (731) will be aligned with crest portion(728) of first cam member (730); and crest portion (728) will drive locktooth (736) of lock bar (762) downwardly into that gap between the twolock teeth (722). Once lock bar (762) is fully engaged with second cammember (731), with lock tooth (736) in the gap between two lock teeth(722), second cam member (731) will be locked into place thus re-lockingarticulation joint (734). Of course, to further articulate end effector(240), the process described above may begin again to unlock,articulate, and re-lock articulation joint (734).

IV. Miscellaneous

It should be understood that any one or more of the teachings,expressions, embodiments, examples, etc. described herein may becombined with any one or more of the other teachings, expressions,embodiments, examples, etc. that are described herein. Theabove-described teachings, expressions, embodiments, examples, etc.should therefore not be viewed in isolation relative to each other.Various suitable ways in which the teachings herein may be combined willbe readily apparent to those of ordinary skill in the art in view of theteachings herein. Such modifications and variations are intended to beincluded within the scope of the claims. It should also be understoodthat the various teachings herein may be readily combined with theteachings of the various references that are cited herein. In addition,the various teachings herein may be readily combined with the teachingsof U.S. patent application No. [Attorney Docket NumberEND7431USNP.0614277], entitled “Method of Unlocking Articulation Jointin Surgical Stapler,” filed on even date herewith, the disclosure ofwhich is incorporated by reference herein; and/or the teachings of U.S.patent application No. [Attorney Docket Number END7446USNP.0614587],entitled “Pivotable Aritculation Joint Unlocking Feature for SurgicalStapler,” filed on even date herewith, the disclosure of which isincorporated by reference herein.

It should be appreciated that any patent, publication, or otherdisclosure material, in whole or in part, that is said to beincorporated by reference herein is incorporated herein only to theextent that the incorporated material does not conflict with existingdefinitions, statements, or other disclosure material set forth in thisdisclosure. As such, and to the extent necessary, the disclosure asexplicitly set forth herein supersedes any conflicting materialincorporated herein by reference. Any material, or portion thereof, thatis said to be incorporated by reference herein, but which conflicts withexisting definitions, statements, or other disclosure material set forthherein will only be incorporated to the extent that no conflict arisesbetween that incorporated material and the existing disclosure material.

Versions of the devices described above may have application inconventional medical treatments and procedures conducted by a medicalprofessional, as well as application in robotic-assisted medicaltreatments and procedures. By way of example only, various teachingsherein may be readily incorporated into a robotic surgical system suchas the DAVINCI™ system by Intuitive Surgical, Inc., of Sunnyvale, Calif.Similarly, those of ordinary skill in the art will recognize thatvarious teachings herein may be readily combined with various teachingsof any of the following: U.S. Pat. No. 5,792,135, entitled “ArticulatedSurgical Instrument For Performing Minimally Invasive Surgery WithEnhanced Dexterity and Sensitivity,” issued Aug. 11, 1998, thedisclosure of which is incorporated by reference herein; U.S. Pat. No.5,817,084, entitled “Remote Center Positioning Device with FlexibleDrive,” issued Oct. 6, 1998, the disclosure of which is incorporated byreference herein; U.S. Pat. No. 5,878,193, entitled “Automated EndoscopeSystem for Optimal Positioning,” issued Mar. 2, 1999, the disclosure ofwhich is incorporated by reference herein; U.S. Pat. No. 6,231,565,entitled “Robotic Arm DLUS for Performing Surgical Tasks,” issued May15, 2001, the disclosure of which is incorporated by reference herein;U.S. Pat. No. 6,783,524, entitled “Robotic Surgical Tool with UltrasoundCauterizing and Cutting Instrument,” issued Aug. 31, 2004, thedisclosure of which is incorporated by reference herein; U.S. Pat. No.6,364,888, entitled “Alignment of Master and Slave in a MinimallyInvasive Surgical Apparatus,” issued Apr. 2, 2002, the disclosure ofwhich is incorporated by reference herein; U.S. Pat. No. 7,524,320,entitled “Mechanical Actuator Interface System for Robotic SurgicalTools,” issued Apr. 28, 2009, the disclosure of which is incorporated byreference herein; U.S. Pat. No. 7,691,098, entitled “Platform Link WristMechanism,” issued Apr. 6, 2010, the disclosure of which is incorporatedby reference herein; U.S. Pat. No. 7,806,891, entitled “Repositioningand Reorientation of Master/Slave Relationship in Minimally InvasiveTelesurgery,” issued Oct. 5, 2010, the disclosure of which isincorporated by reference herein; U.S. Pub. No. 2013/0012957, entitled“Automated End Effector Component Reloading System for Use with aRobotic System, published Jan. 10, 2013, the disclosure of which isincorporated by reference herein; U.S. Pub. No. 2012/0199630, entitled“Robotically-Controlled Surgical Instrument with Force-FeedbackCapabilities,” published Aug. 9, 2012, the disclosure of which isincorporated by reference herein; U.S. Pub. No. 2012/0132450, entitled“Shiftable Drive Interface for Robotically-Controlled Surgical Tool,”published May 31, 2012, the disclosure of which is incorporated byreference herein; U.S. Pub. No. 2012/0199633, entitled “SurgicalStapling Instruments with Cam-Driven Staple Deployment Arrangements,”published Aug. 9, 2012, the disclosure of which is incorporated byreference herein; U.S. Pub. No. 2012/0199631, entitled“Robotically-Controlled Motorized Surgical End Effector System withRotary Actuated Closure Systems Having Variable Actuation Speeds,”published Aug. 9, 2012, the disclosure of which is incorporated byreference herein; U.S. Pub. No. 2012/0199632, entitled“Robotically-Controlled Surgical Instrument with SelectivelyArticulatable End Effector,” published Aug. 9, 2012, the disclosure ofwhich is incorporated by reference herein; U.S. Pub. No. 2012/0203247,entitled “Robotically-Controlled Surgical End Effector System,”published Aug. 9, 2012, the disclosure of which is incorporated byreference herein; U.S. Pub. No. 2012/0211546, entitled “Drive Interfacefor Operably Coupling a Manipulatable Surgical Tool to a Robot,”published Aug. 23, 2012; U.S. Pub. No. 2012/0138660, entitled“Robotically-Controlled Cable-Based Surgical End Effectors,” publishedJun. 7, 2012, the disclosure of which is incorporated by referenceherein; and/or U.S. Pub. No. 2012/0205421, entitled“Robotically-Controlled Surgical End Effector System with RotaryActuated Closure Systems,” published Aug. 16, 2012, the disclosure ofwhich is incorporated by reference herein.

Versions of the devices described above may be designed to be disposedof after a single use, or they can be designed to be used multipletimes. Versions may, in either or both cases, be reconditioned for reuseafter at least one use. Reconditioning may include any combination ofthe steps of disassembly of the device, followed by cleaning orreplacement of particular pieces, and subsequent reassembly. Inparticular, some versions of the device may be disassembled, and anynumber of the particular pieces or parts of the device may beselectively replaced or removed in any combination. Upon cleaning and/orreplacement of particular parts, some versions of the device may bereassembled for subsequent use either at a reconditioning facility, orby a user immediately prior to a procedure. Those skilled in the artwill appreciate that reconditioning of a device may utilize a variety oftechniques for disassembly, cleaning/replacement, and reassembly. Use ofsuch techniques, and the resulting reconditioned device, are all withinthe scope of the present application.

By way of example only, versions described herein may be sterilizedbefore and/or after a procedure. In one sterilization technique, thedevice is placed in a closed and sealed container, such as a plastic orTYVEK bag. The container and device may then be placed in a field ofradiation that can penetrate the container, such as gamma radiation,x-rays, or high-energy electrons. The radiation may kill bacteria on thedevice and in the container. The sterilized device may then be stored inthe sterile container for later use. A device may also be sterilizedusing any other technique known in the art, including but not limited tobeta or gamma radiation, ethylene oxide, or steam.

Having shown and described various embodiments of the present invention,further adaptations of the methods and systems described herein may beaccomplished by appropriate modifications by one of ordinary skill inthe art without departing from the scope of the present invention.Several of such potential modifications have been mentioned, and otherswill be apparent to those skilled in the art. For instance, theexamples, embodiments, geometrics, materials, dimensions, ratios, steps,and the like discussed above are illustrative and are not required.Accordingly, the scope of the present invention should be considered interms of the following claims and is understood not to be limited to thedetails of structure and operation shown and described in thespecification and drawings.

I/We claim:
 1. An apparatus comprising: (a) a body; (b) a shaft assemblyextending distally from the body, wherein the shaft assembly defines alongitudinal axis, wherein the shaft assembly has a distal end; (c) anend effector, wherein the end effector is operable to manipulate tissue;and (d) an articulation joint coupling the end effector with the distalend of the shaft assembly, wherein the articulation joint is configuredto permit the end effector to deflect away from the longitudinal axis ofthe shaft assembly, wherein the articulation joint comprises: (i) alocking assembly operable to selectively lock the angular position ofthe end effector relative to the longitudinal axis of the shaftassembly, and (ii) an unlocking feature operable to selectively unlockthe locking assembly; wherein the shaft assembly further comprises: (i)a first movable member operable to selectively drive articulation of theend effector at the articulation joint, and (ii) a second movable memberoperable to selectively drive the unlocking feature, wherein the secondmovable member is movable independently relative to the first movablemember.
 2. The apparatus of claim 1, wherein the locking assemblycomprises: (A) a first locking member unitarily secured to the endeffector, such that the first locking member is configured to move withthe end effector relative to the longitudinal axis of the shaftassembly, and (B) a second locking member operable to selectively engagethe first locking member to thereby selectively lock the angularposition of the end effector relative to the longitudinal axis of theshaft assembly.
 3. The apparatus of claim 2, wherein the unlockingfeature is operable to selectively disengage the second locking memberfrom the first locking member.
 4. The apparatus of claim 3, wherein theunlocking feature is operable to rotate about a first axis to therebyselectively disengage the second locking member from the first lockingmember.
 5. The apparatus of claim 4, wherein the first axis isperpendicular to the longitudinal axis of the shaft assembly.
 6. Theapparatus of claim 4, wherein the articulation joint is configured topermit the end effector to pivot about a second axis to thereby permitthe end effector to deflect away from the longitudinal axis of the shaftassembly.
 7. The apparatus of claim 6, wherein the first axis and thesecond axis are coextensive with each other.
 8. The apparatus of claim2, wherein the second locking member is configured to translate along alongitudinal path to selectively engage the first locking member.
 9. Theapparatus of claim 8, wherein the longitudinal path of the secondlocking member is parallel to the longitudinal axis of the shaftassembly.
 10. The apparatus of claim 2, wherein the second lockingmember is configured to translate along a transverse path to selectivelyengage the first locking member.
 11. The apparatus of claim 8, whereinthe transverse path of the second locking member is transverse to thelongitudinal axis of the shaft assembly.
 12. The apparatus of claim 1,wherein the first movable member is movable along a longitudinal path.13. The apparatus of claim 1, wherein the second movable member ismovable along a longitudinal path.
 14. The apparatus of claim 1, whereinthe unlocking feature comprises a set of teeth, wherein the teeth haveeither a triangular profile or a square profile.
 15. The apparatus ofclaim 1, wherein the unlocking feature is asymmetric about a centralaxis that runs parallel to the longitudinal axis of the shaft assembly.16. The apparatus of claim 1, wherein the unlocking feature has api-shaped configuration.
 17. The apparatus of claim 1, wherein theunlocking feature has an obliquely oriented wave surface defining aseries of crests and troughs, wherein the crests are operable to providelocking of the locking assembly, wherein the troughs are operable toprovide unlocking of the locking assembly.
 18. The apparatus of claim 1,wherein the end effector comprises a stapling assembly operable to drivestaples into tissue.
 19. An apparatus comprising: (a) a body; (b) ashaft assembly extending distally from the body, wherein the shaftassembly defines a longitudinal axis, wherein the shaft assembly has adistal end; (c) an end effector, wherein the end effector is operable tomanipulate tissue; and (d) an articulation joint coupling the endeffector with the distal end of the shaft assembly, wherein thearticulation joint is configured to permit the end effector to deflectaway from the longitudinal axis of the shaft assembly, wherein thearticulation joint comprises: (i) a first locking member unitarilysecured to the end effector, such that the first locking member isconfigured to move with the end effector relative to the longitudinalaxis of the shaft assembly, (ii) a second locking member operable toselectively engage the first locking member to thereby selectively lockthe angular position of the end effector relative to the longitudinalaxis of the shaft assembly, and (iii) a pivotable unlocking feature,wherein the unlocking feature comprises a pivotable body having a pairof proximally extending projections, wherein the projections define aspace configured to receive a portion of the second locking member tothereby provide clearance for engagement of the second locking memberwith the first locking member, wherein the projections are configured todrive the second locking member away from the first locking member tothereby disengage the second locking member from the first lockingmember in response to pivotal movement of the pivotable body.
 20. Anapparatus comprising: (a) a body; (b) a shaft assembly extendingdistally from the body, wherein the shaft assembly defines alongitudinal axis, wherein the shaft assembly has a distal end; (c) anend effector, wherein the end effector is operable to manipulate tissue;and (d) an articulation joint coupling the end effector with the distalend of the shaft assembly, wherein the articulation joint is configuredto permit the end effector to deflect away from the longitudinal axis ofthe shaft assembly, wherein the articulation joint comprises: (i) afirst locking member unitarily secured to the end effector, such thatthe first locking member is configured to move with the end effectorrelative to the longitudinal axis of the shaft assembly, (ii) a secondlocking member movable along a transverse path to selectively engage thefirst locking member to thereby selectively lock the angular position ofthe end effector relative to the longitudinal axis of the shaftassembly, wherein the transverse path is transverse to longitudinal axisof the shaft assembly, and (iii) an unlocking feature, wherein theunlocking feature is operable to drive the second locking member alongthe transverse path to selectively disengage the second locking memberfrom the first locking member.